Storage battery



prf I4,"l 1931. E. w. SMITH I 1,800,364 i STORAGE BATTERY Original Filed Jan. so, 1922 W 771/555" Edward W @17H/ Patented Apr. 1 4, 1931.

EDWARD w. sM-rrn, or PHILADELPHIA, rENNsYLvANIA STORAGE BATTERY l Application med January 30, 1922,-Seria1 No. 532,726, Renewed October 23, 1928.

I its further object the protection ofthe separators from this action of the peroxide, as

well as the better retention of the peroxide in lace in the supporting grids. l

eference to the drawings will make clearerthe principle of the invention and in the drawings Figure l 1s a horizontal section through a pair of plates showing separators embodying features ofthe invention, and

Figs. 2- and 3 are similarl views showing separators'embodying a modification of the invention;v

` Referring moreparticularly to Figure 1,4

1 is the positive pole plate and 2 the negative pole plate, each shown as consisting of a metallic frame 3 with connecting bars 4 imi bedded in the active material' 5. 6 is a grooved wood separator and '7 is a perforated rubber separator` such as are frequently used in combination.

Under these conditions, however, deterioration of the hard rubber 7 takes place to a marked degree, and further the active material 5 of the positive plate 1 graduallyV soft- 4 ens and percolates through the perforations,

even when these are in the form of very narrow slots.

To prevent both of-these actions, the imperforate inert, finely lporous layer 8 is placed between thevsurface of the positive pole plate, or positive surface, and the separator or retainer, as shown. This layer may consist ofasbestos paper, or material of like characteristics', asbestos being practically inertunderthe conditions indicated.

erforated sheets both kinds being herent thereto. Y

The operation of the applicants combined separator during the useful life of the battery is as follows;

The asbestos sheet is highly porous perf mitting free diffusion of the' electrolyte to all parts of the positive plate but at the same time acting as a retainer for the active material and retarding its dislodgment.: The

vwooden separator is less porous than the.

asbestos sheet but is readily.A oxidized when in contact with the positive plate. This nonporous characteristic is taken advantage ofto prevent particles of active material from the positive plate sifting or filtering through the separator and bridging acrossto the negative plate. These particles will, in time, penetrate through the asbestos rsheetlfrom the positive plate and would-then commence to oxidize the wooden separator were it not for the rubber sheet interposed between the two. This further retards the passage of the particles, and, being less subject to oxidation. than the wood, greatly prolon s the life of the separator and hence the use ul life of the battery. The construction and mode of operation of the modifications shown in Fi s. 2 and 3. are substantially as above descri ed except that Fig. 3 shows a grooved wood separator 6 having-the protective layer 8 adherent to its face, while Fig. 2 shows a perforated rubber sheet' 7 with a similar protective adherent layer 8.-

I claim: f 1. A storage battery separator having a 85 `layer of inert, finely porous material ad.

herent thereto.

2. A storage battery Jseparator consisting of a sheet of perforated hard rubber havin a layer of finely porous, inert material a i 1,800,364v 'i smooth side lying against .the surfacer of of positive and negative pole plates with a 'the negative pole plate,

and a perforated hard rubber sheet located between the layer of-asbestos and the grooved side of the woodseparator. i

5. In .a storage battery. the combination sheet of fibrous material inert to the" oxidizing action of and disposed adjacent to Vthe surface of the positive pole'plate, a Wood diaphragm grooved on one side and smooth on' the other `side and arranged with its smooth side lying against the surface'of the negative pole plate,

sheet located between the sheet ofrubbervWood diaphragm.

and a perforated hard fibrous material and the grooved `,side of the AEDWARD W. SMITH. 

